Despite a foreword full of disclaimers, Greeley's new novel--which laboriously reconstructs the life of Catherine Collins, a nun-activist reportedly tortured and killed by a Latin American dictatorship--reads like an all-out attack on ""liberation theology,"" on priest/nun radicals who give in to the temptation of zealotry, the confusion of political goals ""with the transcendent and the absolute in religious revelation."" The book begins in 1976, less than two years after nun/heiress Cathy disappeared while working with rebel-priest Father Ed Carny (""a Hans Kung with muscles"") in the Salvador-like nation of Costaguana. According to some witnesses, Cathy was indeed horribly murdered by the (now-deposed) junta. According to her last will, she left her fortune to Father Ed's radical crusade. But Greeley's two primary Chicago narrators--Cathy's beloved priest-cousin Blackie Ryan (a cynic) and her lawyer-lover Nick (a romantic)--are determined to keep Father Ed from claiming this legacy: they believe that Cathy became skeptical about the Cause before she vanished. . . and they wonder if maybe she's really still alive. So, while Blackie delivers Greeley-ish tirades against both extremes within the Church, Nick seeks clues in Costaguana--and reads Cathy's diary-like letters, 1962-1974, to Blackie: her teenage embrace of nunhood, despite sexual hunger for sweetheart Nick; her ordeals in the strict canonical no-vitiate (programmed for a church ""that no longer existed,"" says Blackie); her seduction by the ""half-assed"" Church counterculture, by the antiwar activists; noisy radicalism in '68, quitting the hostile order in '69; brief marriage to a rebel-priest (a woman-hating homosexual); the Mission with Father Ed in 1971 Costaguana--but soon followed (after a sexual interlude with Nick) by the realization that ""my whole life has been self-deception. My vocations and my causes and my enthusiasms were all tricks I played on myself and others."" And eventually Nick and Blackie do learn the truth about what happened to Sister Cathy--revealing the cartoon-like monstrousness of Father Ed. . . and the utter phoniness of the martyrdom in Costaguana. Offered in 152 mini-chapters, with the time-frame constantly jerking back and forth, this is a repetitious, disjointed, overlong narrative. Moreover, Cathy--whose misguided fanaticism supposedly stems from rich-girl guilt and sexual repression--is neither especially appealing nor entirely convincing. But, while many readers will object to the portrayal of Catholic radicalism here (Cathy's story is ""not necessarily typical,"" Greeley hedges), others will find it a bracing complement to such novels as James Carroll's Prince of Peace and James Brady's Holy Wars; and Greeley fans, though likely to be disappointed by the lack of full-blooded romance and drama, will find the usual array of testy issues and clerics-in-aspic.